If statement with using reference

I'm want to use references for System.Data.SqlServerCe or System.Data.SqlServer depending on if the user have internet connection or not.

How do i this? Can i declare some kind开发者_如何学C of global variable?

I want to do something like this:

if HASINTERNET

using System.Data.SqlServer

else

using System.Data.SqlServerCe

Your best bet there is to just use DbConnection or IDbConnection, and write a factory method that creates the appropriate type of connection to return (as the more abstract DbConnection / IDbConnection).

Then it will work for any connection type. Be sure to use the connection's .CreateCommand() method etc for creating commands.

Your using is then just using System.Data; (or using System.Data.Common;)

re the actual question; not really. You can do that at compile time, with #if etc - but not at runtime.